Remark : This issue has been first noticed by Alan Kilborn, revisited by Peter Jones and discussed in that topic :

https://community.notepad-plus-plus.org/post/59397

Description of the Issue

When using the Search > Go to... feature, with the Offset option ticked, the different offsets corresponding to each byte of a multi-bytes encoding, after the first one, should be inaccessible !

Steps to Reproduce the Issue

• Open a new tab in N++

• if, necessary, use the Encoding > Convert to UTF-8 to get an empty UTF-8 encoded file

• Just type in the text A👨Z on the first line

Note that, as the emoji MAN 👨 is the Unicode character of code-point U+1F468, we can describe this line, in an UTF-8 encoded file, as :

Characters :   A         👨        Z
Bytes      :   41  F0  9F  91  A8  5A
Offset     :   0   1   2   3   4   5

• If you move the caret right before the A char, the Search > Go to... feature says you're at offset 0

• If you move the caret right before the 👨 char, the Search > Go to... feature says you're at offset 1

• If you move the caret right before the Z char, the Search > Go to... feature says you're at offset 5

All these offsets are correct. But these values should be the only possible offsets to type in in the You want to go to zone !

Actual Behavior

Now, let's force a move to offset 3, exactly in the middle of the multi-bytes sequence of the emoji char ( byte 91 ) and then click on the Go button

• Seemingly, the caret seems right before the Z letter. In fact :

  • If you hit the Backspace key, you get the text Ax91xA8Z, so the first two bytes of the encoding xF0x9F, before the offset, are deleted

  • If you hit the Delete key, you get the text AxF0x9FxA8Z, so the next x91 byte, after the offset, is deleted

• In addition, as you can see, the action of the two keys Backspace and Delete are not symmetrical as the former deletes two bytes ( the beginning of the multi-bytes sequence ) whereas the latter just deletes one byte ( x91 )

Expected Behavior

The offsets values, relative to the individual bytes of a multi-bytes sequence, after the 1 byte, in a Unicode encoded file, should not be allowed ! For instance, in the example above, the allowed values should be, exclusively, 0, 1 and 5

Then, the Backspace and Delete would just act on one character, only, as expected !

Best Regards,

guy038